NYMPHA, a natural product for the conservation of ancient wood

Abstract

In recent years, there has been a significant interest on sustainability and health-safety across various domains. Notably, many traditional chemicals employed in the preservation of Cultural Heritage pose environmental and human health risks. The NYMPHA project aimed to develop an eco-friendly solution using microalgae-derived polysaccharides to remove biological patinas from cultural heritage wooden materials, addressing sustainability and health concerns. To validate its efficacy, the product underwent testing on diverse woods such as silver fir, beech, and sessile oak, selected for their distinct anatomical characteristics. The analytical methodology involves three key steps: 1) determining the optimal extraction and application method through spectro-colorimetric measures and UV imaging; 2) evaluating surface color stability; and 3) assessing the product's effectiveness before and after exposure to a biological attack using spectro-colorimetry. Results indicate that the NYMPHA product can induce a color variation on some wood surfaces. Moreover, although it is reported that algae can have biocidal effects, in this experiment, this action is not observed probably due to the absence of sulphates in the polysaccharide molecule extracted from this specific strain. This emphasizes the necessity for further research and to explore new solutions beyond controlled laboratory conditions, specifically on naturally degraded materials.